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Hey everyone,
Until a year ago I was using a 5″ refractor, and it was OLD school. Nothing wrong with that but I had to give up on it because I just could NOT understand RA and declination.
However one of the main disappointments was that I bought the telescope thinking that I could a really clear view of the planets… particularly Mars Jupiter and Saturn. However the refractor turned out to be a major disappointment in that area as well. To look at the moon with my a 21mm wide field eyepiece… yes it was astonishing. But it does not take much more than a 20×80 pair of binoculars to get a really good look at the detail of our amazing celestial neighbor.
MY point now.. is that for a retirement present my son wants to buy for me, the Celestron Nexstar SE8…. the famous classic Schmidt Cass telescope, introduced with the well known orange optical tube.
Now I am nervous! As much as I am stunned by his generosity, I have reservations about him wasting his money with once again very mediocre and generally disappointing images of my favorite subjects.
I know that aperture equals light gathering power, but I need some assurance that this telescope will outperform the 5 inch refractor… not only for viewing the planets, but in viewing deep sky. I would like to resolve double stars as well. These areas of astronomy have also caught my attention in the year before my retirement and particularly now that I am retired.
The telescope is computer controlled, but that does not intimidate me at all. What DOES concern me is what I mentioned before. I don’t want my boy to waste money if this telescope cannot meet my expectations. In my mind and heart I know that this would be an excellent decision, but in the light of constant disappointment with past experiences, I would appreciate some input from anyone of you folks who can assure me that this decision will be the productive experience I am hoping that it will be.
Ian
Hello Ian,
An 8-inch aperture will certainly outperform a 5-inch, on the planets or anything else. However, aperture is only one consideration. When I first started observing I could not see much fine detail on the planets, even with 8.5-inch and larger apertures. When I moved up to a 14-inch I still could not see the kind of details sketched by Paul Doherty et. al. So, I switched to photography. After a few more years experience I realised that the eye and brain become trained to see finer detail the more you observe. Then I realised how crucial accurate
collimation was. I also realised that the planets rarely look really good unless you observe a lot and catch the good seeing. Observing planets on a laptop screen, when imaging, is a revelation. The details distort every sixtieth of a second with the limb jittering by arcseconds! Then, on maybe 1 night in 20, planets look like a Damian Peach image, when the jetstream is absent and the weather is misty, or even foggy! However, unless the telescope has cooled to the night air and is precisely collimated you still won’t get great views. Moving up from a 5-inch to an 8-inch will not automatically give you good planetary views. So much depends on the state of our atmosphere and how often you observe. On this latter point some sort of user-friendly observatory, that can be set up in minutes, will make you observe 10 times more often, because you can just ‘nip out’ and check the seeing. For planets you do not need a computer control. Despite the hype, low-cost computer controlled telescopes can be more hassle than you need. Planets are easy to find, so a low-hassle Dobsonian is all that is needed… No need for star-alignment, cables and pressing buttons…just push the Dob and look through the finder….Deep Sky objects are obviously easier to find with ‘Go To’, but star-hopping is simple for the brightest objects.
So, to summarise, moving up to an 8-inch will not give you spectacular planetary views unless you observe a lot, train your eyes and brain, and keep the telescope collimated and cooled to the night air. The bigger the better though, so it may be worth thinking about a Dob. You can get a 12-inch Skywatcher Go To Dob for the same price as a Celestron 8SE, but you’d want to build a small run-off shed to house it, or put it on wheels. Deep Sky objects would look far brighter in a 12-inch! One final thought….Mars, Jupiter and Saturn are horribly low down at the moment so whatever telescope you get you have a long wait until they are nice and high again.
And the best views are usually obtained when planets are high up.
Martin
Ian, further to martin’s excellent advice. Try visiting a local astronomical society on one of their open evenings. My local society holds monthly meetings when society members bring along their telescopes to view whats on offer in the sky for members of the public. If your lucky telescopes similar to what your considering may well be available to look through together with an experienced observer providing some initial instruction.
Regards,
Eric
Thank you gentlemen,,,, you both make a good point. I will not dispute my son’s decision to buy the Celestron. I need portability because I /we plan on travelling to locations on the other side of the mountains to areas where the skies are amazing and very dark. I live in Washington Sate in the US, And there are some really good observing sites.
I will admit to being skeptical due to the decisions I have made in the past. I didn’t want to admit that the telescope was NOT really good quality… I was being cheap and miserly lol. This time I plan on being more careful about quality. I am referring to the eyepieces I will purchase as accessories. My son plans on buying the Celestron and I must try and bury my past skepticism, as well as lack of knowledge and patience.
Ian
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